No matter how great Nadal was - I now really doubt whether he can make his comeback even closely successful compared to what he did before.
This is not mainly because of his age but more of the fact he was absent for such a long time. No matches, no competition, for many many weeks no training and last but not least, not being on the tour and perhaps having a life outside of that surely must change Nadals point of view somehow?

So my question is - as I am only medium familiar with tennis history:What was the greatest comeback by any tennis player after being absent for more than 6 months?
This means no matches at all, not just skipping the grand slams or dropping out of the rankings!

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No matter how great Nadal was - I now really doubt whether he can make his comeback even closely successful compared to what he did before.
This is not mainly because of his age but more of the fact he was absent for such a long time. No matches, no competition, for many many weeks no training and last but not least, not being on the tour and perhaps having a life outside of that surely must change Nadals point of view somehow?

So my question is - as I am only medium familiar with tennis history:What was the greatest comeback by any tennis player after being absent for more than 6 months?
This means no matches at all, not just skipping the grand slams or dropping out of the rankings!

do you mean biggest comeback considering long-term playing or the first tournament played ?

It doesn't matter, because few players in history can compare to Nadal (what other players have won the career grand slam at the age of 24 in the open era, and in the same year winning slams on clay, grass and hard-court?). I wouldn't be surprised if Nadal took an 8-month absence and had the best year of his career. And Nadal can make a great start by winning Acapulco (which he did in 2005).

It doesn't matter, because few players in history can compare to Nadal (what other players have won the career grand slam at the age of 24 in the open era, and in the same year winning slams on clay, grass and hard-court?). I wouldn't be surprised if Nadal took an 8-month absence and had the best year of his career. And Nadal can make a great start by winning Acapulco (which he did in 2005).

I'm going with Kim Clijsters. Retired, had a baby, decided to come back two years later. In her third tournament of her comeback she won the US Open unseeded, eventually made it back to #1 in the world.

I'm going with Kim Clijsters. Retired, had a baby, decided to come back two years later. In her third tournament of her comeback she won the US Open unseeded, eventually made it back to #1 in the world.

^^^^^
This is the winner...

But the WTA has had several comebacks after 6+ month lapses. Monica Seles and Jennifer Capriati are comparable examples. Both of the Williams sisters have had comebacks after long layoffs. Goolagong came back after she had her baby.

As for the ATP tour, vive le beau jeu ! provided a pretty comprehensive list of the men's comeback players from the past 30 years. What is interesting is that I believe that only Agassi, Krajicek, and Muster ended up winning any Slams after such extended breaks, and those Slam wins took some time to pull of. Most of the other guys just seemed to lose some steam after being away so long. I believe Delpo has another Slam in him, but notice how long it's taken him to get back to the level where he's competitive. As great as Nadal is, I don't see him contending right away, and we'll see if he has the same heart to fight that has separated him in the past.

Another interesting note is about Muster's knee injury. He was hit by a drunk driver, and his leg was crushed under the bumper of a car. Both his ACL and MCL ligaments were severed, and had such massive abrasions down the length of his leg, he had to be hospitalized for fear of infection. He wore a cast that extended from his ankle to the top of his thigh for 3 months. This video shows some of the rehabilitation Muster did in order to come back:

Muster's injury occurred on April 1st, 1989. His first comeback match on the ATP tour was on September 19th, 1989, which he won. That represents a 170 day break between matches, and less than 6 months. In contrast, Nadal's injury seems to be much less severe (with surgery to help repair a tear - not a rupture - on the patellor tendon)... yet, Nadal has been off the tour for 184 days now, and isn't scheduled to play again for at least another 57 days. This makes me think that there is more to Nadal's absence than just knee pain. I'm not talking about a "silent ban" but more likely a lack of passion to get back on tour. Muster was hitting balls from a wheel chair, but all the pictures I've seen of Nadal so far show him lounging on a boat, getting a tan, and fishing. I think the guy is burned out, and is not in a rush to get back. Unlike Muster, who was cut down just after breaking into the top 10, Nadal doesn't have anything to prove - which does not bode well for a return to top form.